Safety grip device for elevators



(No Model.) 3 Smetssheet 1. l y H. R. SMITH.

SAFETY GRIP DEVICE FOR BLEVATORS.

Patented Dec. 1,8, 1894.

www.

(No Model.) 3 Sheets- Sheet 2.

11. R. S11/11TH. SAFETY GRIP DEVICE POE ELEVATORS. No. 530,971. Patented 1160.18, 1894.

VIII/117'" 3 sheetssheep 3.

(No Model.)

H. R. SMITH. SAFETY GRIP DEVICE POR ELBVATORS.

Da-530,971. Patented Deo. 18, 1894.

NITED STATES PATENT OFFICE.

IIUMPHREY R. SMITH, OF CHICAGO, ILLINOIS.

SAFETY GRIP DEVICE FOR ELEVATORS.

SPECIFICATION forming part of Letters Patent N o. 530,971, dated December 18, 1894.

Application filed April 23, 1894. Serial No. 508,679. (No model.)

To all whom t may concern.-

Beit known that I, HUMPHREY R. SMITH, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Safety Grip Devices for Elevators, of which the following is a specification.

This invention relates to elevator apparatus and its object is to provide an improved governor controlled safety grip, simple and effective, and automatic in operation.

A further object is to lprovide a safety grip construction which can be operated from the car when occasion requires.

With these objects in view the invention consists in the construction, combination, location and relative arrangement of parts, as will be more fully hereinafter described, as shown in the accompanying drawings and finally pointed out in the appended claims.

In the drawings forming a part hereof Figure l is a bottom plan View, parts being in horizontal section'of an apparatus embodying the principles of my invention. Fig. 2 is a side elevation of the construction shown in Fig. 1. Fig. 3 is a longitudinal sectional view taken on the line y, y, Fig. 1, looking in the direction of the arrows. Fig. 4 is a transverse sectional view taken on the line x, Fig. l, looking in the direction of the arrows. Fig. 5 is an enlarged detail View in bottom plan. Fig. 6 is a vertical central longitudinal sectional view of the parts shown in Fig. 5, taken on the line z, a, looking in the direction of the arrows. Fig. 7 is a partial detail view in side elevation showing a modified form of mechanism for controlling the gripping jaws. Fig. Sis a View similar to Fig. 2, taken from the opposite side of Fig. l. Fig. 9 is a detail view, partially in section, the parts being broken away and parts omitted, showing the governor in the act of tripping trip latch T. Fig. 10 is a detailed transverse sectional View, illustrating a means for adjusting weight 18. Fig. 11 is a partial detail View, the parts being in horizontal section, illustrating the action of trip T.

The same reference sigllS are used to designate the same parts wherever they occur throughout the several views.

Reference sign 1 designates the vertical guides, which are arranged in pairs, and extend on opposite sides throughout the length of the elevator shaft. These guides may be of any desirable shape, adapted to be gripped by the gripping jaws hereinafter described. In the form shown they comprise T shaped bars, the stem of the T portion projecting inwardly'in position to be gripped by the gripping jaws when occasion requires, but it is obvious that any other form of safety guide may be employed, andthe guides may be of any suitable or desirable material.

Reference sign 2 designates the floor of the car. On the under side of the car door is secured in any suitable manner what I designate a safety plank, 7, to which are segovernor attachments hereiuafterdescribed. Safety plank 7 is of suitable length and thickness to solidly support the several mechanisms hereinafter referred to, and itextends across the bottom of the car and the ends cured the safetygrip,cont rolling, tripping and thereof are grooved to receive the stem of T guides l, as shown.

While I have shown, and, in practice, prefer to use a safety plank upon which are mounted and securedthe several mechanisms comprising my safety grip apparatus, it will be readily understood that such plank can/8o vided with vertically perforated iianges, 3, 3,

see Figs. Sand 4, whiletheinner ends of said web are formed into wings, 4, 4, for a purpose presently to be described. A bolt, P, is received in the Vertical perforations in iianges 3, 3, of web W, and forms the pivot for the gripping jaws, J, J, which are in the form of levers, pivoted intermediate their ends by means of interlocking ianges, 5, 5, 6, 6, to each other and to bolt P, as shown. The outer end of said lever is formed into a jaw, of extended surface and is arranged in proximity to the side of the stem of T guide l. A pair of said levers being arranged at each end of the safety plank, constitute a pair of gripping jaws adapted, when occasion requires, to grip the guides, and arrest the movement of the IOO car, as will more fully hereinafter appear. The rear ends of gripping jaw levers J, J, eX- tend parallel with flanges 4, 4, of web W, and interposed between each lever J and the face of each flange 4 of said web isa set of strong spiral springs, S, the tendency of which is to separate the1 rear ends of said levers, and thus cause the front or gripping ends to grasp the T flange of guide l. By this arrangement it will be seen that the rear end of each gripping lever is acted on by two sets of springs, and in practice I prefer to employ two spiral springs in each set, constituting a double coil, as indicated in dotted lines in Fig. 2, thus producing an exceedingly effective construction whereby a strong grip on the guide rails is effected.

I will now describe the mechanism for holding the gripping jaws open, and springs S, compressed. B designates a short rock shaft passing through a perforation in the floor 2 ofthe car and, safety plank 7, centrally of the length of the latter. Upon this shaft, and adapted to turn therewith is a cam shaped block C, and also the hub of an arm A. A suitable washer or block 8, may be interposed between the under surface of the safety plank and the top surface of the hub of arm A, in order to offset cam C sufficiently to bring the said cam approximately in line with the eX- treme rearwardly projecting ends of gripping jaws J, as shown, for a purpose presently to be explained. Suitablypivoted to the under surface of plank 7 is a trip latch T, having a hooked toe, adapted to engage and hold the end of lever A, in a position to retain springs S compressed, and consequently gripping jaws J, J, open through the following described apparatus: Pivoted to each web W is apair of levers L. To each lever L intermediate the ends thereof is pivoted alink 8, and each link 8 is pivoted, in turn, to the inner end of a jaw J. The inner end of each lever L is connected by means of a link 10, to the end ofa rod R, thus constituting a toggle arrangement, so that when rods R are moved endwise the inner ends of each pair o." jaws J, J, are simultaneously moved toward or away from each other. The object of this arrangement is to hold the gripping jaws open by drawing the inner ends thereof together, thus compressing the springs S, by moving rods R longitudinally toward the end of the safety plank. The rods R are held in position to secure the compression of the Isprings S by arm A and trip latch T through the mechanism now to be described.

The inner end of one of the rods R is slotted, as indicated at 1l, and at its extreme inner end carries a pin or projection which, as in the construction shown, may be, and preferably is, a friction roller, D. The inner end of the rod R extending from the opposite pair of jaws is bent, as shown at I2, to clear the extreme inner end of the slotted rod, and its inner end is received in the said slot 11, and it carries a similar pin, projection or friction roller D. By this construction it will be seen that each rod R serves to guide the other in its longitudinal movement. Friction rollers D, D are arranged on dametrically opposite sides of cam plate C, for a purpose presently to be explained.

I will now describe the construction and operation of the governor whereby the trip latch T is operated to release the end of lever A, in order to permit the springs S to act upon the rear ends of gripping jaw levers J and cause said gripping jaws togrip guide l.

Journaled to a suitable stud or pin on the under side of safety plank 7, or, in case no safety plank is provided, to the under side of the car floor, is the ordinary governor G, around which leads a cable E for operating the same. Said cable is also led around suitable guide pulleys, I, I. The cable E, guide pulleys I, I, and the governor G are arranged in the usual manner, the cable being station' ary andv revolving the governor as the car travels up and down in the elevator shaft. Pivoted in or to the governor disk G, is a dog K. A light spring I-I may be employed to retain the dog within the governor disk, but when the governor disk is rapidly rotated, as when the lifting cable of the car breaks, and the car begins to fall to the bottoni of the shaft, the end or toe of dog K is forced by centrifugal action beyond the periphery of the governor disk G and in position to strike a projection M, see Fig. 2, on trip latch T, and thus trip the same and release the end of arm A, when through the action of the springs S, the gripping jaws, J. J. grip guides l, and arrest the fall of the car.

I shall designate generically the mechanism for tripping the trip-latch as the tripping mechanism.

Shaft B is extended up [lush with the top side of the car floor, and its end may be squared or a squared socket may be provided therein adapted to be engaged by a suitable wrench, which may be carried in the car as will be readily understood by reference to Fig. 2. The object of this arrangement is to permit the conductor to ease the car down to a landing by suitably manipulating shaft B, in case the fall of the car is arrested by the automatic tripping and gripping devices above described between the landings. It will be seen that this object is accomplished by suitably manipulating shaft B through rods R and the toggle links connecting the same to the inner ends of gripping jaw levers J, J, whereby the inner ends of each pair of gripping jaws may be simultaneously drawn together against the action of springs S. This I consider an important feature of my inven-` tion, as thereby the car is enabled to be expeditiously brought to a landing and the frightcned passengers unloaded therefrom.

It frequently happens that serious and often fatal accidents occur in elevators, without the breaking of the hoisting ropes or cables, by the conductor losing control of his car, as

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when the valve mechanism gets out or order or fails to operate properly, causing the car to descend rapidly, frightening the passengers who, seeing the car is out of control, seek to escape by jumping from the rapidly descending car. In order toprovide against such a contingency Iprovide trip latch T with an arm 15, see Fig. 1, to which I pivot a lever, 16, which may extend in any suitable way into the car, and in position to be convenientto the conductorf By this arrangement the gripping mechanism may be operated from the car by the conductor in case the governor fails to act properly, or in case he loses control of his car. By manipulating the lever 16, the gripping mechanism may be operated independently of the governor.

In Fig. 7 I have shown a modified form which, in many cases I prefer to use. In this construction I dispense with the use of cam C, and in place thereof I provide a horizontally arranged short shaft 17, upon which is mounted a sleeve having arms projecting in opposite directions. To each arm is pivoted a rod R. so as to swing vertically when released, instead of horizontally, as in the construction above described. A weight, 18, adjustable in in any suitable way as by sliding the same along arm A may be provided to overcome the friction of the link connections of rods R to the sleeve on shaft or stud 17, so that when the end of said arm is released from trip latch T', the entire power of the compressed springs S is applied to jaws J, J.

A chain or other suitable connection, 20, may be secured to the end of arm A and lead into the car in order to afford a convenient way to reset the trip latch. By suitably manip ulating chain 20, jaws J, J, after being set to grip the guides 1, can be relieved whereby the car can be eased down to alanding when its motion is arrested between the landings,

as will be readily understood.

In practice I prefer to apply the entire gripping, controlling and governing mechanisms to safety plank 7, and then secure said plank to the bottom of the car. This arrangement possesses advantages and is convenient in handling and in transportation,but, as above explained, it may be an object to reduce weight, or for other reasons it may be desirable to dispense with the use of said plank. In such case the mechanisms above described may be applied directly to the floor of the car.

While I have shown and described in detail a specific form of apparatus for carrying out the principles of my invention, I desire it to be understood that I do not limit myself thereto, as many changes and variations would readily suggest themselves to one skilled in the art, without departing from the spirit or scope of my invention.

Having now fully described the principles of my invention anda form of apparatus embodying the same, what I claim as my own Arm A is held in the trip latch T',

invention, and desire tosecure byLetters Patent of the United States, is

1. In an elevator apparatus gripping jaws, a trip latch for holding the same in open position, a governor for automatically releasing said trip latch, and auxiliary means i'ndependentof the governor for releasing said trip latch; as and for the purposeset forth.

means for holding the same4 in open position,

a governor for automatically releasing said holding means to set said jaws, and means, operated from the car, for rocking said jaws about their pivots, thereby temporarily releasing the jaws after they are set, whereby the car can be eased down to a landing; as

and for the purpose set forth.

4. In an elevator apparatus, gripping jaws, means for-holding said jaws in open position against a spring pressure, a governor for automatically releasing said holding means to set said jaws, in combination with an auxiliary means independent of the governor for releasing said' holding means; as and for the purpose set forth.

5. In an elevator apparatus, gripping jaws, a means for 4holding said jaws in open position, a governor for automatically tripping said holding means in combination with an auxiliary tripping mechanism, adapted to be operated from the car and independent of the governor and means, also to be operated from the car and independent of the governor and of said auxiliary tripping mechanism, for tem- IOO porarily relieving said jaws after they are set;

to release said lever; as and for the purpose set forth.

7. In an elevator apparatus, a guide, a pair of pivoted gripping jaws, springs normally adapted to press said jaws against said guide, a trip latch, an arm adapted to be held by said latch, connections between said arm and jaws comprising a system of toggle levers, and a governor for automatically tripping said trip latch; as and for Vthe purpose set forth.

8. In an elevator apparatus, a pair of guides, a pair of jaws adapted to grip each guide, springs adapted to act on said jaws, a trip latch, an arm adapted to be held thereby, a

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system of levers adapted to simultaneously set said jaws, connections between said arm and levers and a governor for automatically tripping said arm; as and for the purpose set forth.

9.In an elevator apparatus, guides, jaws adapted to grip the same, springs engaging said jaws normally tending to close the same, a trip latch, an arm adapted to be engaged thereby and to hold said jaws against the action of the springs, a governor for automatically tripping said latch, and auxiliary means independent of said governor for tripping said latch, operated from the car, comprising an arm connected to said latch and a lever connected to said arm and extending into the car; as and for the purpose set forth.

l0. In an elevator apparatus, a gripping mechanism, a tripping mechanism for automatically setting the same, and means, independent of the tripping mechanism, for temporarily releasing said gripping mechanism, comprising a rock shaft arranged to extend into and adapted to be operated from the car, and connections between said shaft and said gripping mechanism for operating the latter from the former; as and for the purpose set forth.

11. In an elevator apparatus, grippiugjaws comprising pivoted levers, arranged in pairs, springs adapted to press against said jaws to normally close the same, a tripping mechanism for automatically setting said jaws, and means operated from the car for temporarily releasing said jaws after being set comprising a system of levers connected to said jaws for simultaneously moving the same, a shaft leading into the car and connections between said shaft and levers; as and for the purpose set forth.

12. In an elevator apparatus a gripping mechanism, a tripping mechanism for auto matically operating the same, comprising a speed governor a safety plank for supporting said mechanism and governor, said plank adapted to be secured to the Hoor of an elevator car; as and for the purpose set forth.

13. In an elevator apparatus a safety plank adapted to be secured to the Hoor of an elevator car, gripping devices carried at each end of said plank, a tripping mechanism for setting said tripping devices, comprising a speed governor, also carried by said plank, and guides arranged in the elevator shaft in proximity to the ends of said plank, adapted to be gripped by said gripping devices when operated by the tripping mechanism; as and for the purpose set forth.

14:. In an elevator apparatus a gripping mechanism comprising levers having extended gripping surfaces on their outer ends, said levers being arranged in pairs, a solid web arranged between each pair o f levers, said levers being pivoted to each other and to said web, sets of springs arranged between said web and levers, arranged inside of the pivot, and normally tending to close the gripping jaws, means for retaining said jaws in their open position and means for releasing said gripping mechanism; as and for the purpose set forth.

15. In au elevator apparatus, a gripping mechanism, a tripping mechanism therefor, and means for temporarily releasing said gripping mechanism When set comprising a rock shaft having one end thereof extending into the car and flush with the iioor thereof, whereby said shaft may be rocked from the car, and levers connected to said gripping mechanism and operated by said shaft; as and for the purpose set forth.

In witness whereof I have hereunto set my hand, this the 20th day of April, 1894:, in the presence of two subscribing Witnesses.

HUMPHREY R. SMITH.

Witnesses:

W. E. CARR, EARL PARcnLLs. 

